Abstract:Abstract: The water quality of aquaculture is a key factor concerning the economic benefits of aquaculture and the quality of aquatic products. In recent years, with the development of economy, the discharge of industrial wastewater and domestic sewage has greatly increased, resulting in environmental pollution, for example, the water quality of aquaculture ponds has been polluted. In order to achieve the goal of high yield and safe breeding at the same time of environmental protection and energy conservation, scholars have paid attention to the rapid and accurate acquisition of aquaculture water quality information, which was the important research content of the smart agriculture and agricultural Internet of Things. Water quality monitoring technology based on spectral analysis is an important development direction of aquaculture water quality monitoring. Compared with traditional chemical analysis, electrochemical analysis and chromatographic analysis methods, spectral analysis technology is more simple and convenient, consumes a small quantity of reagents, and is reproducible. This article summarizes and sorts the existing domestic and foreign research literatures, and systematically analyzes and discusses the important parameters of water quality monitoring, data preprocessing methods, feature band extraction, and detection model algorithms based on spectroscopy. This article reviews the COD (chemical oxygen demand) water quality monitoring methods, total nitrogen water quality monitoring methods, total phosphorus water quality monitoring methods, heavy metal water quality monitoring methods, covering traditional chemical methods and spectral analysis methods of these parameters. This article compares and analyzes the spectral method and the traditional methods. We find that compared with the traditional water quality monitoring methods, the spectral technology is non-invasive, rapid rapid?monitoring, repeatable and accurate. The sensitive spectral bands of the above parameters are summarized. The data preprocessing algorithm includes Savitzky-Golay smoothing, wavelet analysis, and multivariate scatter correction, the feature band extraction algorithm includes continuous projection algorithm, no-information variable elimination algorithm, and principal component analysis, and the model includes partial least squares algorithm, least squares algorithm, and artificial neural network. The advantages, disadvantages and scopes of application of these algorithms are summarized and compared. The spectrum detection process of these algorithms is analyzed. Among them, a detailed review of the application of model algorithms in water quality monitoring is conducted, and the prediction results of each water quality prediction model algorithm are statistically analyzed. The results show that online aquaculture water quality testing will be the focus of research. Multi-parameter monitoring is the development direction of aquaculture water quality monitoring. For the processing of spectral data, the combination of multiple data processing algorithms will still dominate. Nonlinear modeling will become the mainstream method for water quality data analysis of aquaculture and will become the mainstream method for the application of spectral technology to water quality detection of aquaculture.